A Midsummer’s Equation by Keigo Higashino

‘A Midsummer’s Equation’ is Keigo Higashino’s 3rd novel featuring Tokyo detective Shunpei Kusanagi and his friend physics professor Manabu Yukawa, sometimes known as Detective Galileo.

Yukawa has travelled to the small seaside town of Hari Cove. DESMEC (Deep Sea Metals National Corporation) are hosting a conference about their proposed exploration of Hari Cove in an effort to appease environmental groups. Yukawa is there to help explain some of their equipment. He is staying at the old and rundown Green Rock Inn.

The Inn is owned and run by Shigehiro Kawahata and his wife Setsuko, assisted by their 30 year old daughter Narumi. They have been joined for part of the school holidays by their year 5 nephew Kyohei. There is one other guest at the Inn – Tsukahara. The Inn, like the rest of the town, is struggling to survive as people choose more glamorous resorts for their holidays. Kyohei and Yukawa become fast friends as the professor tries to teach the boy why science is important in life.

Then Tsukahara dies. His death is initially considered to be an accident, but on further examination it looks more like murder.

The local police seem fairly inept, even with large numbers on the case. While Kusanagi investigates Tsukahara’s life in Tokyo, Yukawa looks into his death in Hari Cove. Why was he in Hari Cove and why did he choose the Green Rock Inn.

Kusanagi’s and Yukawa’s investigations take them back to another crime that occurred 15 years earlier. They find information that Tsukahara searched for for many years. This eventually leads them to the reason for Tsukahara’s death.

The ending was a complete surprise to me.


I have loved all of the novels in this series – ‘The Devotion of Suspect X’ and ‘Salvation of a Saint’. This novel was equally good.

The characters are excellently portrayed and the feelings of calmness, politeness and respect come through very clearly in Higashino’s writing.

The stories are very clever and the solutions are never quite what I expect.

I look forward to seeing more of Keigo Higashino’s work in English translation.


Book Published 2011

Book Published in English 2016


See a full list of books by Keigo Higashino

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Filed under Book Reviews, Crime, Detective, Higashino, Keigo, Mystery, Series Fiction

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